Current designs of chain drive systems in a machine use a sprocket to drive the chain. The sprocket is typically a circular member with teeth positioned on its periphery to engage the link retaining pins of the chain. The chain is driven to perform a source of work in a machine such as a conveyor system or a track-type tractor. For example, a track-type tractor has a chain that encircles a portion of and is driven by a sprocket. Some of the problems encountered with a sprocket and chain drive system is noise and vibration and what is known as chordal action. Chordal action is defined as a rise and fall of the chain links, of the engaging portion of the chain, in a radial direction from the center of the sprocket as each of the pins are engaged by and through rotation of the sprocket. Rise is defined as travel of the links in an outwardly radial direction from the center of the sprocket as each one of the pins engages the sprocket and is carried through a portion of rotation of the sprocket. Fall is defined as the travel of the links in an inwardly radial direction toward the center of the sprocket through the remaining portion of rotation of the sprocket. The rise and fall of the chain links induces an oscillating motion in the non-engaged portion of the chain. During the fall motion of the chain, each of the pins to be engaged by the sprocket will impact the sprocket as it is engaged, thereby causing noise, vibration and wear.
The present invention is directed to overcoming one or more of the problems as set forth above.